Feeding and first folding unit in a wrapping machine

ABSTRACT

FEEDING AND PRIMARY FOLDING UNIT FOR A MACHINE FOR WRAPPING PILES OF PLATE-LIKE ARTICLES. THE FEEDING PART OF THE UNIT COMPRISES A CONVEYOR BELT WHICH CARRIES THE PILES TO BE WRAPPED UNTIL THESE ABUT AGAINST A STOP MEMBER. SUBSEQUENTLY THE PILES ARE PUSHED LATERALLY WITH RESPECT TO THE CONVEYOR BELT BY A PUSHER WHICH TRANSFERS THEM ONTO THE FREE END OF A PAPER TAPE UNWOUND FROM A BOBBIN. THE PILE AND THE PAPER TAP ARE THEN GRIPPED BY A PINCER MEMBER AND DRAWN IN THE PRIMARY FOLDING PART OF THE   UNIT. AFTER CUTTING OF A WRAPPING SHEET FROM SAID TAPE THE WRAPPING OF THE PILE TAKES PLACE. FOR THIS PURPOSE A CARRIAGE IS PROVIDED WHICH FIRSTLY BENDS UPWARDLY THE PORTION OF THE WRAPPING SHEET NOT ENGAGED BY THE PILE AND THEN, ADVANCING ON THE PILE, LAYS IT THERE ON.

Jan. 19, 1971 v GENTlL] Q 3,555,771

FEEDING AND FIRST FOLDING UNIT IN A WRAPPING MACHINE Filed June 9, 1969 3 Sheets-Sheet 1 AMT 1M4 AGENT Jan. 19, 1971 v E -11L 3,555,777

FEEDING AND FIRST FOLDING UNIT IN A WRAPPING MACHINE Filed June 9, 1969 3 Sheets-Sheet 2 VITTORIO GENTILI AGENT v. GENTILI 3,555,777

FEEDING AND FIRST FOLDING UNIT IN A WRAPPING MACHINE Jan. 19, 1971 3 Sheets-Sheet 5 Filed June 9, 1969 INVENTOR. vmomo cnmu Rani J- AGENT United States Patent Int. Cl: B65b 11/08 US. Cl. 53-209 6 Claims ABSTRACT OF THE DISCLOSURE Feeding and primary folding unit for a machine for wrapping piles of plate-like articles. The feeding part of the unit comprises a conveyor belt which carries the piles to be wrapped until these abut against a stop member. Subsequently the piles are pushed laterally with respect to the conveyor belt by a pusher which transfers them onto the free end of a paper tape unwound from a bobbin. The pile and the paper tape are then gripped by a pincer member and drawn in the primary folding part of the unit. After cutting of a wrapping sheet from said tape the wrapping of the pile takes place. For this purpose a carriage is provided which firstly bends upwardly the portion of the wrapping sheet not engaged by the pile and then, advancing on the pile, lays it there on.

BACKGROUND OF THE INVENTION The present invention relates to a feeding and primary folding unit for machines designed to wrap plate-like articles, particularly sheets of paper and the like.

The wrapping of pile of plate-like articles is connected with considerable difficulties during the first wrapping steps in which the piles of articles are each placed on a wrapping sheet, and when the first folding steps of the wrapping sheet are performed. These difficulties are particularly enhanced when the plate-like articles to be wrapped are of large size and are not rigid, as for example large sheets of paper of polythene.

Various kinds of machine are known for wrapping such piles of articles but either they have a low production rate or the wrapping which they effect is of poor quality.

In fact it may be noted that, due to the fact that wrapping machines presently in use for wrapping such groups of articles are extremely heavy and of very delicate working, the operational steps which prevent relative movement between the sheets of each pile and between the piles and the relative wrapping sheets are performed very slowly. This evidently has an adverse effect on the wrapping rate of the machine but even so the possibility exists of relative movement, both when the pile of sheets is placed on the wrapping sheet and when the primary folding of the wrapping sheet is effected. However the main disadvantage of the commercially known machines is that they carry out a slow and consequently rather weak wrapping due to the deformation which the pile of sheets undergoes during the first steps of the wrapping cycle.

The main object of the present invention is that of providing a feeding and primary folding unit for machines designed to wrap piles of laminar articles which substantially eliminates the disadvantages described above due to the fact that said unit has a relatively high wrapping speed by virtue of the structural arrangement of the members which cause the various movements of the piles of articles to be wrapped.

Another object of the invention is that of providing a feeding and primary folding unit which ensures the continuous control of the articles during their movement.

Another object of the invention is that of providing a 3,555,777 Patented Jan. 19, 1971 "ice unit of the described type which does not cause any deformation of the piles of articles during the steps in which the first folding of the relative wrapping sheet is carried out, and which does not have any sliding between its component parts, so that sturdy or tight packages are obtained.

Another object of the invention is that of providing a wrapping unit which can be readily adjusted to deal with pile of articles of different dimensions, the operational speed of this unit being inversely proportional to the size of the piles to be wrapped.

SUMMARY OF THE INVENTION These and other objects, which will appear more clearly hereinafter are attained by a feeding and first folding unit for a machine for wrapping piles of plate-like articles, comprising a conveyor belt for said piles, means for feeding a paper tape for wrapping said piles, a displacement member acting transversely to said conveyor belt for partially superposing a pile onto said tape, a pincer member arranged to grip said pile and the wrapping paper and complete the passage of said pile from said conveyor belt to said first folding unit, means for cutting a sheet from said paper tape when said passage is completed, and wherein the first folding unit comprises a carriage including a slidable framework, and rollers mounted on said framework for receiving wound thereon a belt, sliding guides for said framework carried by supports which are raisable and lowerable means for raising or lowering said supports, means arranged to move to and from the carriage on said sliding guides, when the carriage is in raised position, means also being provided for actuating the belt of the carriage and causing the advance of the piles to a further folding unit.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will appear more clearly from the following detailed description of a preferred embodiment of a wrapping unit according to the invention, illustrated by way of example in the accompanying drawings in which:

FIG. 1 is a longitudinal section of an apparatus for feeding piles of articles to be wrapped taken along the line II of FIG. 2;

FIG. 2 is a cross-sectional view of the apparatus of FIG. 1; taken along line II-II of FIG. 1;

FIG. 3 is a longitudinal section of an apparatus for carrying out the first folding operations of a wrapping sheet taken along line IIIIII of FIG. 4;

FIG. 4 is a cross-sectional view of the apparatus of FIG. 3 taken along line IV-IV of FIG. 3; and

FIG. 5 is a diagrammatic plan view of the wrapping machine which includes the feeding and folding apparatus shown in FIGS. 1 to 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to said figures, reference numeral 1 generally indicates an apparatus for feeding the piles of articles to be wrapped and reference numeral 2 indicates a unit which feeds and supports the wrapping paper in which the piles of articles are to be wrapped. Reference numeral 3 indicates a cutting device and at 4 there is shown the first folding station or unit of the wrapping machine.

The apparatus 1 (FIGS. 1 and 2) comprises a framework -5 which is provided at its top with two rows of transoms or cross-members 6 and 7 which support two rows of longitudinal wooden rods 8 and 9.

On the wooden rods 8 and 9 there is supported a conveyor belt 10 which is wound on rollers 11, 12, 13, 14 and 15 of which the rollers 13, 14 and 15 form a belt stretching unit. The roller 11, which is the roller of largest diameter, is keyed on a shaft on which there is also keyed a pinion 16. A chain 17 is wound on said pinion 16 and on a wheel 18 fast with the slow shaft of a speed reduction unit 19 driven by an electric motor 19b. Between said wheel 18 and said slow shaft of the speed reduction unit there is interposed a progressive engagement clutch 19a which is secured to the fixed framework of the apparatus.

In the top portion of the framework 5, adjacent the roller 11 there are arranged two supports 20 and 21 to which there is secured a member 22 (shown in crosssection in FIG. 1) which lies transverse to the direction of motion of the conveyor belt and arranged to stop the piles carried by said belt. In the upper portion of the framework 5 there is also arranged a pair of cylindrical rods 24 and 25 which act as sliding guides for a device 26 which is arranged to cause the transverse sliding movement of the piles along said member 22. The device essentially comprises a pneumatic jack 27 screwed to a threaded sleeve support 28 which, through a screw and a handwheel 29, can be positioned within certain limits, transverse to the conveyor belt 10.

The stem of said jack 27 acts on a kind of blade 30 which is arranged to engage the pile 23 and push it towards a unit 31 of the feeding apparatus. Below said unit 31 a roller 32 is arranged above which there slides a paper tape 33 which is unwound from a bobbin 34 ("FIG. 5). The purpose of said unit 31 consists in braking the tape 33 and in maintaining it tight in order to avoid wrong folding operations. The bobbin 34 is moved by a row of parallel transmission belts 34a arranged near its periphery and driven by an electric motor 34b. Before passing beyond said roller 32, the free edge of said paper tape 33 passes below the active branch of the conveyor belt 10 (FIG. 2).

On the framework 5 of the pile-feeding apparatus 1 there is also secured an electric motor 36 which, through belts 37 and a brake clutch 38, drives a reduction unit 39. On the slow shaft of the reduction unit 39 there is keyed a crank 40 which carries at its free end a roller 41 which in turn is arranged in a groove 42 of a lever 43. Said lever 43 is pivoted on a vertical pin 44. The other end of the lever 43 is connected by means of a jack 45 and a rod 45a to pincers 45b (FIG. 5). The pincers 45 are not shown in detail in the drawings, since they are of common type. They may for example comprise two levers which, under the action of a jack, seize the pile of paper 23 in the position opposite to the one they have in FIG. 5 and transfer it to the first folding station 4 along a channel 450. It will be observed that in order to permit the seizing of the pile, the latter will be partially pushed on the tape 33 by the unit 26.

The first folding station (FIGS. 3 and 4) forms the inlet portion of the wrapping machine proper. This station comprises a framework 46 and driving units 47, 48 and a third driving unit (not shown). These driving units actuate the first folding apparatus 49 (FIG. 3). Said first folding apparatus includes a pair of shafts 50 and 51 arranged transverse to the machine framework for rotation, or partial rotation, about their own axes. On the shafts 50 and 51 there are rigidly mounted pairs of arms 52 and 53 which remain adjacent the sides of the machine framework. With the interposition of pins, said pairs of arms support two by two cylindrical guides. More precisely the two right-hand arms support a cylindrical guide 54 and the two left-hand arms support a guide 55 (FIG. 4).

Adjacent the pair of arms 52 the guides 54 and 55 are provided with oblong slots designed to couple with said arms and permit the rotation of the arms and the vertical movement of the guides, as will be explained hereinafter.

On the guides 54 and 55 there is slidably arranged a carriage generally indicated at 56. The carriage '56 comprises a frame 57 which carries at its ends a pair of rollers '58 and 59 on which there is wound a belt 60. On the shaft of the roller 59 and on a pinion 61 arranged adjacent the roller 58 there is wound a chain 62. Said chain 62 is also wound on a trio of pinions 63, 64 and 65 which are pivoted in a box 66 which is anchored by means of a ring member 66a to a bar 66b laterally secured by stirrups 66c to the frame 57 of the carriage. The bar 66b is slidably guided in the ring member 66a, while the box 66 is prevented to move longitudinally by means of a pair of angular members 66d attached to the framework 46 of the folding unit, which, however, permit the vertical displacement of the carriage 56. With this arrangement, supposing that the carriage 56 is caused to slide along the relative guides 54 and 55 and that the diameter of the pinion keyed on the shaft of the roller '59 is equal to the diameter of the rollers 59 the belt 60 will advance, during the sliding of the carriage, at the same speed as the latter. The sliding of the carriage along the guides 54and 55 follows an upward vertical movement thereof and the rest position of the carriage is at a lower level.

, The vertical movement of the carriage 56 is controlled by the driving unit 47 which, together with members which will be described hereinafter, causes the raising of the guides 54 and 55. In fact, as previously stated, the guides 54 and 55 are carried by the arms 52 and 53 keyed on the transverse shafts 50 and 51. On an intermediate portion of said shafts 50 and 51 there are also secured arms 67 and 68 which are connected by connectingrods 69 and 70 to a lever 71 pivoted to a support 72 arranged in the lower portion of the framework 46. The connecting rods 69, 70 are articulated to the lever 71 on either side of the suppport 72 in which said lever is pivoted so that the movement of the pair of arms '52 and 53 which carry the guides 54 and 55 is equal. On the opposite side to that in which it'is articulated to the connecting rods 69 and 70, the lever 71 has a groove 73 in whichthere rotates a roller 74 carried by a crank 74a keyed on the slow shaft of a speed reduction unit 75. Said reduction unit is connected to a brake clutch 76 whose inlet shaft' carries keyed thereon a speed variator unit 77 which is transmissively connected to a motor 79 by means of a belt 78. The speed variator unit is of the type with variable diameter pulleys and for this reason the speed reduction unit and the brake clutch are mounted on a slide 80 which the carriage 56 is raised before advancing. The carriage is advanced by the driving unit 48 which comprises, in

manner identical to that of said driving unit 47, a motor 86, a speed variator device 87, a belt 88, a brake clutch 89 and a speed reduction unit 90 whose slow shaft has a crank 91 keyed thereon. The driving unit 48 has (as already described in the case of the driving unit 47) the reduction unit 90 and the brake clutch mounted on a slide 92 parallel to the slide 80. The unit 48 differs from the unit 47 only in that the speed changer 87 is keyed directly on the shaft of the motor 85 instead of the inlet of the brake clutch 8-9. The crank 91 acts on a lever 93 by means of a roller carried at the free end of the former and engaged in a suitable groove provided on the lever.

Y The lever 93 is pivoted to a support 94. Through a connecting rod 95 having one end pivoted to a support 96 fixed to the carriage 56, the lever 93 controls the silding of the carriage 56. I

Besides the belt 60 and the relative support and control members, the carriage 56 comprises a flat transverse member 97 which extends along all the width of the carriage.

The member 97 is secured to a pair of tubular members 98 which are slidable with respect to the carriage since they are housed in bushes received in the rear portion of the carriage. The member 97 is urged to egress forwards, with respect to the carriage 56, by a pair of weights 99 (only one of which is visible in FIG. 3) which act on the tubular members 98 by means of a flexible member 100. The flexible member 100 is wound,,sta rting from the weight 99, first over a pulley 101, carried by one of the arms 52, and then over a pulley 102 carried by one of the arms 53. The egressing of the tubular members 98 is prevented by a plate 103 secured to the rear of each of said members 98 and engaging the frame 57 of the carriage 56.

One of the trio of rollers 63, 64 and 65, which as stated are supported by the box 66, also constitutes the terminal portion of the third driving unit of the carriage 56. More precisely, the pinion 64 is fast with a conical pinion 104 which meshes with a corresponding pinion 104a (FIG. 4) which is keyed on a shaft 105, the latter projecting from the bottom portion of the box 66. On the shaft 105 there is coupled one end of a telescopic shaft 106 which extends to a shaft 107 which projects from the top of a box 108. As may be seen from FIG. 3, a pair of conical pinions is arranged in the box 108; the first of these conical pinions is keyed on said shaft 107 and the second conical pinion is keyed on a shaft 108a which is the cyclical shaft of all the machine. The shaft 108a is driven by a driving-Variator-brake-clutch unit which is identical to the units 47 and 48.

The lever 71, which, as said, causes the raising of the carriage 56, also controls the raising of a stop member 109 which is normally opposite the flat member 97. The stop member 109 is supported by a pair of cylindrical upright rods 110 which are subject to the action of the forked ends of arms 111 keyed on a transverse shaft 112. The latter also carries an arm 113 which is connected to said lever 71 by means of a connecting rod 114. When the stop member 109 is in the lowered position it is inserted in a groove 115 of a conveyor belt 116, said groove being obtained by the double deviation of the belt 116 by means of a trio of rollers 117. The belt 116, which is driven by the motor which also drives the shaft 108a, is the member which displaces the piles to be wrapped along the machine. Said belt 116 begins in a position immediately adjacent the channel 460 transverse to the machine along which the pincers (not shown) move. Adjacent the channel 460 of the pincers there is arranged a plurality of transverse rollers 118 which act as supports for the piles 23 which are at the same level as the upper branch of the belts and 116. At this level there also arrives the wrapping paper which is unwound from the bobbin 34 and passes above the roller 32 (FIG. 2). At the same level there are arranged the upper portion of the belt 60 and the stop member .109 when the carriage 56 and the stop member 109 are in the lowered position. In this manner the paper tape 33, from which there are formed wrapping sheets for each pile by means of the cutting unit 3 (of which FIG. 3 shows only the sliding supports 119 and 120 and the upper transom 121), reaches the first folding station in flat condition. Reference numeral 122 (FIG. 3) generally indicates the members (shafts, conical pinions and screws) which cause the adjustment of the speed variator units inserted in the machine and permit the adjustment of the machine in order to operate with dififerent dimensions of piles of paper to be wrapped. At the same time it is possible to vary the work rate of the machine, i.e. the strokes of the moving members of the machine by varying the point of action of the various cranks on the various levers.

The working of the feeding unit and the first folding unit is very simple. The piles of paper fed on the belt 10 of the feeding unit are spaced from one another since the speed of the belt 10 is greater than that of the belt which carries the piles to the belt 10. When one of the piles strikes the transverse stop member 22 it causes the closure of an electric contact (not described previously) which starts the sequence of the passage of the pile from the belt 10 to the primary folding station and onto the relative wrapping sheet. This electric contact, in fact, initially causes the actuation of the jack 27, the consequent advance of the pile of paper transverse to the belt 10 by the pusher 30, until the edge of the pile of paper adjacent to the belt 116 overlaps a narrow lateral portion of said belt on the plane defined by the transverse rollers 118 and the belt 60. At this moment the belt 60 lies at the same level of the belt 116, while the stop member 109 is inserted in the groove 115. Thereafter the motor 36 and the jack causes the advance of the pincers 45b along the channel 450 and the subsequent closure of the pincers the gripping of the paper tape 33 and of the pile of paper to be wrapped. Subsequentl the same members 36, 45 cause the pincers 45b to return towards the rest position which is exactly opposite, with respect to the wrapping machine proper, to the pile feeding unit of FIGS. 1 and 2 and the piles of paper to be wrapped are passed to the first folding station.

When the pile of paper has reached the primary folding station, and immediately after the cutting of the paper tape 33 by the cutter 3, the driving unit 47 is actuated causing the rotation of the lever 71 and consequently, through the connecting rods 69, 70 and 114, the rotation of the arms 52, 53 and 111, whereby the carriage 56 and the stop member 109 are raised. The consequence of the raising of the carriage 56 is that the sheet of paper tape 33 is bent to assume the form of a flat S, a portion of which remains under the pile of paper 23, while the free portion is on the belt 60. The other free portion of the sheet of paper tape 33 is retained between the stop member 109 and the front face of the pile of paper 23, so that it extends vertically above said pile. The carriage 56 is then caused to advance by actuating the driving unit 48 which, through the lever 93 and the connecting rod 95, pushes the carriage 56 on the guides 54 and in order to superpose it to the pile of paper 23. As a result of the advancing of the carriage 56 the rear face of the pile is knocked up by abutting engagement with member 97. At the same time the portion of the wrapping sheet, which was previously above the belt 60, is gradually layed and slightly pressed on the pile without any relative sliding. Indeed, since the rollers 63, 64 and 65 are not actuated, the belt carries out an advancing movement on the pile 23 like that of a caterpillar track. When the advance of the carriage 56 has been completed (the advance being such that the roller 59 arrives adjacent the stop member 109), the belt 116 and the belt 60 are respectively below and above the pile of paper to be wrapped and the driving unit which drives the belt 116 not only causes the belt 116 to travel but also actuates the transmission means of the belt 60, which, as said, comprises the shafts 108a, 107, 106 and 105, and the conical pinions meshing with the pinion 64. The rotation directions of the belts 60 and 116 are concurrent, so that the pile 23 of paper may be pushed under the stop member 109, which causes the folding of the second edge of the wrapping sheet onto the pile, and transferred by the belt 116 through the second folding station, where the wrapping is completed. Said second folding station which is generally indicated by the reference numeral 123 in FIG. 5, is of known type and is provided with folding members comprising two pairs of opposite folders 124 and 125, which execute the folding of the wrapping sheet onto the lateral faces of the pile.

What is claimed is:

1. A feeding and first folding unit for a machine for wrapping piles of plate-like articles, comprising a conveyor belt for said piles, means for feeding a paper tape for wrapping said piles, a displacement member acting transversely to said conveyor belt for partially superposing a pile onto said tape, a pincer member arranged to grip said pile and the wrapping paper and complete the passage of said pile from said conveyor belt to said first folding unit, means for cutting a sheet from said paper tape when said passage is completed, and wherein the first folding unit comprises a carriage including a slidable framework, and rollers mounted on said framework for receiving wound thereon a belt, sliding guides for said framework carried by supports which are raisable and lowerable, means for raising or lowering said supports, means arranged to move to and fro the carriage on said sliding guides when the carriage is in raised position, means also being provided for actuating the belt of the carriage and causing the advance of the piles to a further folding unit.

2. A unit according to claim 1, in which said means arranged to move to and fro the carriage on said sliding guides comprises a lever pivoted to the machine framework and subject to the action of a crank member keyed on the output shaft of a rotary motion source, said lever having one end connected to the carriage.

3. A unit according to claim 1, in which said sliding guides comprise cylindrical bars the ends of which are supported in respective levers rigidly mounted on a pair of transverse shafts, said transverse shafts each having a further arm connected by means of a connecting rod to a lever pivoted to the machine framework and subject to the action of a crank member keyed on the onput shaft of a rotary motion source, said further arms being connected to said lever on either side of the pivot of said lever, in order to cause the raising or lowering of the carriage.

4. A unit according to claim 2, in which said sources of rotary motion comprise an electric motor, anchored to the machine framework, a speed variator of the type with variable diameter pulley connected to said motor by means of a belt, a brake clutch unit and a speed reduction unit, said speed reduction unit and said brake clutch unit being mounted on'slides.

5. A unit according to claim 1, in which the means for actuating the belt of the carriage comprise two pinions, one of which having a diameter equal to that of a support roller of said belt, a chain wound over saidpinions and over a trio of pinions at least one of which is connected to a source of rotary motion by transmission means comprising at least one telescopic shaft and conical wheels, said source of rotary motion being also arranged to drive the belt means for advancing the pile tothe further folding units.

6. A unit according to claim 1, in which said carriage is provided below said belt with a flat trans-verse member parallel to the rollers of said belt, said flat member being secured to a pair of tubular members slidable in the ad vance direction of the carriage and loaded by weight means so as to cause it to advance with respecttto said THERON E. CONDON, Primary Examiner N. ABRAMS, Assistant Examiner 

